1. Field of the Invention
This invention relates to a processing assembly for performing a given process, a fixing device for fixing toner on a sheet, and an image forming apparatus.
2. Description of the Related Art
Mechanical equipment often allows a component or a portion of the equipment to be removed for maintenance and inspection. For example, photocopiers, printers, fax machines, and other image forming apparatuses are exemplified as such equipment.
An image forming apparatus typically comprises a fixing device configured to fuse and fix toner to a sheet. The fixing device comprises an immobilizing mechanism configured to immobilize a position of the fixing device in a housing of the image forming apparatus. A user may operate the immobilizing mechanism to unlock and then remove the fixing device to outside of the housing of the image forming apparatus.
As described above, the fixing device generates heat in order to fuse toner. A particular fixing device has a color changing portion configured to change color according to the heat from the fixing device, in order to secure safety for a user. The user may visually recognize temperature of the fixing device, and more safely replace the fixing device.
In general, unnecessary operation on mechanical equipment is undesirable. For example, when the immobilizing mechanism of the fixing device is unnecessarily or unintentionally operated, the immobilized position of the fixing device may be released, which results in unintended movement of the fixing device. This may detract usual functions of the fixing device.
The above-described fixing device with the color changing portion may give a user some caution. However, when the user does not notice a change in color of the color changing portion, or does not recognize the meaning of the color change, the caution by the color change is not effective.